1. Technical Field:
The present invention relates broadly to an improved hemodialysis system, and more particularly relates to a hemodialysis system utilizing a pulsatile flow blood pump.
2. Description of the Prior Art:
Commonly, in the prior art pertaining to hemodialysis, steady flow pumps typified by a Sarns 3500 Roller Pump are used to pump the dialysate and the blood in the system.
Also known in the prior art are pulsatile flow blood pumps used for cardiac assistance and replacement and in cardio-pulmonary bypass devices. Examples of the prior art pulsatile flow pumps are disclosed in U.S. Pat. Nos. 4,004,299; 4,058,855; 4,143,425; and 4,293,961, issued to Thomas M. Runge.
The objective of this invention is to significantly improve the efficiency of the hemodialysis process by eliminating the prior art steady flow blood pump and replacing it with a pulsatile flow pump, whereby hemodialysis is caused to more closely simulate the natural blood purification process performed by kidneys in conjunction with the pulsatile flow pumping action of the heart. Laboratory test results indicate that by using a pulsatile flow blood pump for hemodialysis, urea is cleared from the blood approximately three times as fast as it is cleared in the prior art system utilizing a steady flow blood pump, while more desirable larger molecular weight blood constituents, such as vitamin B.sub.12, are cleared from the blood less rapidly and therefore tend to be retained in the blood.